6. Physical properties
Germanium looks like a metal. It has a bright,
shiny, silvery color. But it is brittle and breaks apart
rather easily, which metals normally do not do. It
has a melting point of 937.4°C (1,719°F) and a
boiling point of 2,830°C (5,130°F). It conducts an
electric current poorly. Substances of this kind are
called semiconductors. Semiconductors conduct an
electric current, but not nearly as well as metals
like silver, copper, and aluminum.
7. Germanium is a relatively inactive element. It does
not dissolve in water and does not react
with oxygen at room temperature. It does dissolve
in hot acids and with oxygen at high temperatures,
however. It becomes more active when finely
divided. It will combine
with chlorine and bromine to form germanium
chloride (GeCl 4 ) and
germanium bromide (GeBr 4 ).
9. Reaction of germanium with air
Ge(s) + O2(g) GeO2(s)
*Reaction of germanium with water
*Reaction of germanium with the halogens
*Reaction of germanium with acids
*Reaction of germanium with bases